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The technology of hards concrete developed in this study differs primarily by the binders - semi-burnt dolomite, related to magnesia cements. Grouting fluid is bischofite (MgCl2) or magnesium sulfate (MgSO4), density 1.2 g/cm3. One of the ways of strengthening and adding new properties to hards concrete, which can significantly expand its application domain, is an introduction of chrysotile to the concrete composition. The best specimen have density 570-585 kg/m3, strength 14.5 - 15.1 MPa and low thermal conductivity (0.065-0.074) W/(m·K), what allow them to serve as structural and thermal insulation material. Sound absorption coefficient is from 0.17 to 0.6 (at audio frequencies of 125-2000 Hz). Frost resistance exceeds 50 cycles, water absorption is 40-50%, shrinkage is less than 0.4%, fire stability is 0.75-1.54. Based on the results obtained, it can be concluded that the material is most applicable in low-rise construction. The developed material will solve the problem of utilizing of industrial hemp waste from textile production and dolomite waste in the form of a magnesian binder, thereby reducing the cost of the material in compare with existing world analogues.

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The crucial task up to date is to find effective solutions to expand the raw material base of the construction industry by involving local natural and man-made raw materials instead of traditional expensive energy-intensive materials. An inexhaustible source of raw materials can be mining waste, such as dolomite and lime. Currently, they are large-tonnage industrial deposits that limit the area of development. The problems of strengthening man-made cohesive soils for the manufacture of wall materials, and their use as natural bases is also front and center. The optimal compositions of soil-concrete mixtures based on waste carbonate deposits are selected. The goal of this work was to design a composition of a complex binder for strengthening clay soil. The second goal of the work was to obtain masonry soil-concrete products. For this purpose, waste from the dolomite production of the Melekhovsky deposit was used. To solve the problems, authors carried out such tests as chemical analysis, mineralogical analysis, X-ray phase analysis, raster electron microscopy, compressive strength test, frost resistance test, and water resistance test. Comparing the obtained results, it is now becoming apparent that the compositions of GD-4 and GD-5 at close density values have high strength characteristics at design age. The content of dolomite waste above 30% leads to an increase in strength, the best results are achieved with a dolomite content of 34.6-45.3%, in this range also with increasing binder content, water absorption and density increase, and therefore porosity decreases. The phosphates that make up the composite increase its water resistance.

In this paper we tested mechanical aspects of chemical reactions as means to fortification of clay soil. We also tested properties of soil-concrete using waste of dolomite and chrysotile asbestos. The composition and properties of the composites are presented along with the comparison with traditional reinforced cementing materials. Main testing means of properties were method of x-ray phase analysis, electric scanning microscopy, soil strength changes and soil internal friction angle changes.